Technological advancements have contributed to an increased popularity in remotely piloted vehicles (RPVs) which are frequently used in game applications. These RPVs may include drones in the form of planes and multi-rotor hovercrafts, as well as land vehicles and marine vehicles.
Popular game applications for RPVs may include racing and pursuit games. These games generally involve a number of players each with his own RPV system which includes two stations, a first station the RPV, for example a drone, and the second station a remote control base unit for controlling the drone. Some systems may include a display on the remote control base unit to view the images and other information which may be received from the drone while other systems may include viewing glasses which may be worn by the player or other display means in addition to, or in lieu of, the display on the base unit.
A major problem encountered in game applications involving a number of players and multiple numbers of RPV systems is spectrum sharing, that is, how to allocate frequencies to the multiple systems so that they do not interfere with one another due to their geographical proximity. An example of such an interference situation is shown in FIG. 1 which schematically illustrates a typical game application scene 10 with multiple RPV systems and interference sources.
In game application scene 10 which may be a RPV racing scene, two RPV systems 12A and 12B are shown in geographical proximity. RPV system 12A includes an RPV 14A and a remote control base unit 16A and RPV system 12B includes RPV 14B and a remote control base unit 16B. Uplink and downlink communication may include control data on the uplink, and video and other data which may be related to the operational status and/or position of the RPV on the downlink. In RPV system 12A, communications between RPV 14A and remote control base unit 16A may be over CH1, represented by bidirectional arrow 18A, where CH1 may be a same channel for the uplink and downlink communications, or may represent two different channels, one for the uplink and one for the downlink. In RPV system 12B, communications between RPV 14B and remote control base unit 16B is over CH2, represented by bidirectional arrow 18B, and where CH2 may represent similarly to CH1 a same channel for the uplink and the downlink or one channel for the uplink and another channel for the downlink. and where in some cases, CH1 and CH2 may be at the same frequency or proximal to one another to result in interference. Transmissions from base unit 16A or from RPV 14A may cause interference 22 in CH2, as indicated by hatched arrow 18B, and may affect the performance of RPV system 12B. Additionally or alternatively, other RF transmissions may cause interference, for example, from a radar station 20 which may cause interference 24 in CH2.
Systems have been developed which attempt to solve the problem of inter-channel interference between RPV systems. In one such system, an RPV system upon detecting channel interference from another RPV system or from a radar system, may switch to a better channel which provides the best uplink and/or downlink quality. This is indicated in FIG. 1 by bidirectional arrow 18C which represents new, interference free CH3 to which RPV system 12B has switched. As with CH1 and CH2, CH3 may represent a single channel for both the uplink and downlink, or two separate channels (one for uplink and one for downlink).